text: 	/**
  	Controls the mask that covers the subject during a step transition
  
  	@class SubjectMask
  	@@singleton
  	**/
  	Mask.SubjectMask = jazz.Class().extending(FadableItem).singleton;
  
  	/**
  	Renders the subject mask
  
  	@method render
  	**/
  	Mask.SubjectMask.method("render", function() {
  	    this.$el = $("<div>").addClass("sideshow-subject-mask");
  	    this.callSuper("render");
  	});
  
  	/**
  	Updates the dimension, positioning and border radius of the subject mask
  
  	@method update
  	@param {Object} position                              The positioning information 
  	@param {Object} dimension                             The dimension information 
  	@param {Object} borderRadius                          The border radius information 
  	**/
  	Mask.SubjectMask.method("update", function(position, dimension, borderRadius) {
  	    this.$el
  	        .css("left", position.x)
  	        .css("top", position.y)
  	        .css("width", dimension.width)
  	        .css("height", dimension.height)
  	        .css("border-radius", borderRadius.leftTop + "px " + borderRadius.rightTop + "px " + borderRadius.leftBottom + "px " + borderRadius.rightBottom + "px ");
  	});